Electric heateb



' 1,629,744 May 24, 1 927. H. N. SHAW ELECTRIC HEATER Filed March 1. 1926 za INVENTOR.

B ZJAW A TTORNEYS Patented May 24, 1927.

UNITED STATES HAROLD N. SHAW, OF MILW'AUKEE l -WISCONSIN.

Application filed March This invention relates to improven'ients in electric heaters, and more particularly to controllers for the same.

It is one of the objects of the present invention to provide an electric heater for cooking and other purposes arranged with a. controller to provide for three degrees of heat.

A further object of the invention is to provide a heater oi the class described in which the controller is in the "form of a readily removable and three-way adjustable plug.

A further object of the invention is to provide an electric heater controlled so that the current can be caused to pass through all or part of the resistance or heating element.

A further object of the invention is to provide an electric heater of the class described which is strong and durable, very light in construction, eiiicient in operation, and well adapted for the purpose described.

Vith the above and other objects in view the invention consists of the improved electric heater and controller and its parts and combinations as set forth in the claims and all equivalents thereof.

In the accompanying drawing in which the same reference characters indicate the same parts in all of the views:

Fig. 1 is a plan view of the improved electric heater and controller;

Fig. 2 is a. longitudinal sectional view thereof taken on line 2-2 oit Fig. 1;

Fig. 3 is a detail view of the controller, the dotted lines showing the plug in two positions of adjustment;

Fig. 4 is another detail view of the controller, the dotted lines showing the plug in athird position of adjustment; and

Fig. 5 is an enlarged detail sectional view taken on line 55 of Fig. 4.

Referring now more particularly to the drawing it will. be seen that the numeral 8 indicates the frame of the heater which is of circular form and closed at its inner end by a plate 9 to which a handle 10 is secured, the handle being spaced from. the plate by collars 11. A reflector plate 12 is mounted within the heater frame and its bottom surface is engaged by an insulating block 13. The insulating block is removably retained in position by means of a U-shaped legcr supporting rod 14 which is pivotally carried by the curved portion 15 of the plate 9. The

. ELECTRIC HEATER.

1, 1926. Serial No. 91,517.

outer end portions of the rod 14: yieldingly engage a looped portion 16 extending from the frame to releasably lock the insulating block and U-shaped leg in position.

A wire resistance or heating element 17 of usual construction is mounted within the trame above the reflector plate, as shown in Fig. 1, and about insulating spools 18. A plurality of spaced, horizontal bars 19, sup porting the spools, form a grid or utensil support.

Extending through the plate 9 are threeterminals 20, 21, and 22 arranged in a triangular torniation and a lead wire is secured to each terminal. Lead wire 23 connects one end of the heating element with the terminal 20, lead wire 2a connects the other end of the heating element with the terminal 22, and the intermediate portion of the heating element is connected with the terminal 21 by a lead wire 25.

Each of the terminals 20, 21, and 22 is formed with an elongated shank portion extending outwardly through the medial portion of the handle and suitably insulated therefrom. Pivotally mounted on the shank portion or one of the terminals, as 22, is a bracket member 26. The end portions of said bracket member abut against and are suitably insulated from a collar 27 of substantially triangular form pivotally mounted about and enclosing the shank portions of the terminals. The collar is adapted to be turned slightly and a turn of the same will pivot the bracket 26 and cause a yielding brush contact portion 28 to engage an extension of the terminal 20, as shown in Fig. 5.

A plug 28, of usual construction, may be pushed into the collar 27 to engage any two terminals as indicated in Figs. 3 and 4;, the dotted lines showing the positions of the plug with respect to the terminals. The usual circuit wires extend from the plug for connection with a source of electricity.

In use, the cord carrying the plug 28 is connected with a source of electricity and it it is desired to have the electricity flow through the entire resistance unit 17, the

plug 28 is inserted into the member 27 so as to engage the terminals and 22. hen

so connected the current flows through the connection 23, the resistance unit, and is returned through the connection 24:. It a greater intensity of heat is desired, the plug is inserted so as to engage the terminals a Fig. 5.

is broken by and 21 and in this arrangement only a portion of the resistance unit is utilized, as the current will pass through the connection 25 and through the resistance unit to its medial point where it will be returned through the connection 23 to the terminal 21. A third adj ustment is also ossible providing for a still greater intensity of heat. To secure this adjustment. the collar 27 is given a slight turn to the left until the brush 28 contacts with the terminal 20, as shown in The plug is then inserted so as to engage the terminals 21 and 22. Due to the fact that the brush, in this position of adjustment forms a connection between the terminals 20 and 22, the current will flow through both of the connections 23 and 24 into the resistance unit and at the medial portion thereof it will be returned through the connection 25.

It should also be noted that the electrical connection between the brush 28' and the terminal 20 must be positively made before the plug can be pushed to engage the terminals 21 and 22 and this connection cannot be broken until after the supply circuit entirely removing the plug. l urthermore, it is impossible to make the foregoing connection when the plug engages either the terminals 20 and 22 or the terminals 20 and 21. This arrangement eliminates the possibility of either an are or short circuit occurring in the connector.

From the foregoing description it will be seen that the improved electric heater and controller is of very simple and novel construction, and is well adapted for the purposes setforth.

. WVhat I claim as my invention is:

1. In an electric heater having an elongated resistance unit, a plurality of terminals, a connection between one terminal and one end portion of the resistance unit, a connection between another terminal and the other end portion of the resistance unit, another connection between a third terminal and an intermediate portion of the resistance unit, and an adjustable member movably mounted on one of said terminals to join one of the end connections with the other end connection.

An electric heater, comprising a frame, a reflector plate held therein, an insulating block adjacent the lower face of the reflector, a pivotally attached supporting base holding said block and releasably engaging said frame, an elongated resistance unit within the frame and supported above the exposed face of the reflector. three spaced apart terminals extending outwardly from the frame, a connection between one terminal and one end portion of the resistance unit, a connection between another terminal and the other end portion of the resistance unit, a connection between the third terminal and an intermediate portion of the resistance unit, a collar movably surrounding said terminals, a brush mounted on a terminal in connection with an end portion of the resistance unit and movable with said collar to contact with the terminal in connection with the other end portion of the resistance unit, and a plug selectively engageable with adjacent pairs of said terminals.

3. In an electric heater having a.i'esistance unit, three terminals extending from the resistance unit and connected to different port-ions thereof so that circuits may be completed through the resistance unit to produce a high heat, a low heat, or a medium heat, a

a plug engageable with adjacent pairs of said terminals, means for positively cmmeeting the ends of the resistance unit before the plug can be adjusted with respect to the terminals-to the high heat position, said a means also serving to positively hold the connection thusmade until the plug is removed, and means for positively preventing a connection between the ends of the resistance unit when the plug is engaging the terminals in either the medium heat or low heat position.

In testimony whereof, I atlix my signature.

HAROLD N. SHAW. 

